Electronic components whether individually or combined on a printed circuit board, can and do fail. Testing, repairing and replacement often times is a laborious, time consuming, procedure by skilled technicians that provide service in well equipped laboratories or repair facilities. Usually even the simplest electronic device must be sent to a centrally located repair center when a defect is suspected or known. After the suspect part arrives at the repair center, it is taken in turn, repaired and returned to the user. This is a time consuming procedure that creates a downtime for the electronic components associated with the defective part. As is sometimes the case, the suspected part is not in fact the one that is defective so that yet another period of non-operation for the associated electronics is in store while the truly defective part is sought out, sent to the repair facility, repaired and returned.
Production facilities cannot tolerate this type of downtime. Duplication of electronic controls, processing and associated components is not cost effective where capital expenditures are excessive. Furthermore, heavily trafficked activities such as those associated with avionics, mass transportation control and the like simply cannot afford to be inoperable for any appreciable time due to faulty electronics. Rescue, medical and military applications all have human lives depending upon the reliability of a wide variety of electronics and associated devices. These situations simply cannot be put on hold but must proceed as best they can usually in remote places and in unfavorable conditions.
Where in site repairs have been attempted, the prior methods utilize mechanical toggle switches, variable phase controls, variable transformers and combinations of the same which produce destructive transient voltage spikes to many modern, sophisticated, integrated circuits. Generally speaking, the line level voltages which are coupled to the instruments under test produce excessive electrical noise and in addition to the voltage spikes can be hazardous to solid state components.
Thus, there is a continuing need in the state of the art for a portable work center having essential testing and repair capabilities that does not generate destructive signals for circuits such as those associated with modern integrated circuit boards.